Cerebral blood flow reorganization

ABSTRACT

An implantable device includes an outer tubular member defining a longitudinal axis and a lumen. The outer tubular member includes: an outer wall portion having a plurality of first strands defining a plurality of first openings therebetween, the outer wall portion having a first porosity; and an inner baffle portion disposed within the lumen, the inner baffle portion including a plurality of second strands defining a plurality of second openings therebetween, the inner baffle portion having a second porosity that is lower than the first porosity of the outer wall portion.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a divisional application of U.S. PatentApplication No. 16/468,530, filed on Jun. 11, 2019, now U.S. Pat. No.11, 241,323, which is a National Stage Application under 35 U.S.C. §371(a) of PCT/US2017/066248, filed on Dec. 14, 2017, which claims thebenefit of and priority to U.S. Provisional Application Ser. No.62/434,116, filed on Dec. 14, 2016. The entire disclosures of all of theforegoing applications which are incorporated by reference herein.

BACKGROUND

Tinnitus is an auditory perception of sound in the absence of anexternal source. Tinnitus affects more than 50 million Americans. Theimpact of tinnitus is high, due to the cost of diagnosing and treatingtinnitus as well as the high levels of comorbid debilitating psychiatricillnesses associated with tinnitus. Lives of patients suffering fromtinnitus can be severely impacted, and it is not uncommon for patientsto suffer from insomnia, depression, or even have suicidal ideations.

Tinnitus may be pulsatile and non-pulsatile. Although difficult totreat, non-pulsatile tinnitus may be treated using deep brainstimulation (“DBS”) and transcranial magnetic stimulation (“TMS”).Pulsatile tinnitus is rhythmic and accounts for about 10% of tinnituspatients. Pulsatile tinnitus may be just as debilitating asnon-pulsatile tinnitus. There are many causes of pulsatile tinnitus, butthe common mechanism of sound generation is attributed to flow patternsin blood vessels near the cochlea, the sound sensing cavity of the innerear. In particular, pulsatile tinnitus may be caused by abnormalpulse-synchronous blood flow in vascular structures disposed near thecochlea, such as, transverse sinus, sigmoid sinus and internal jugularvein (“SSIJ”). The vascular structures with abnormal flow may be eithervenous or arterial. Approximately 40% of pulsatile tinnitus etiologiesare due to abnormal venous flow, approximately 35% are due to arterialabnormalities, with the remainder of the cases being unidentified.

Unfortunately, not all cases of pulsatile tinnitus are treatable. Inaddition, the risks of conventional pulsatile tinnitus treatments may begreater than the risks of the underlying disease. Conventional pulsatiletinnitus treatments include endovascular or open surgical occlusion of alaterally-projecting out-pouching from the sigmoid sinus, termed adiverticulum. Other treatment options include open surgical resurfacingof the sinus, which has a risk of postoperative complications as high as23% and may result in venous sinus thrombosis, which could lead tointracranial hemorrhage, facial swelling, and wound dehiscence. Thus,therapeutic options may be more dangerous than the underlying disease,especially when the disease carries essentially no risk of stroke orhemorrhage. Accordingly, there is a need for improved treatment methodsand devices for treating pulsatile tinnitus.

SUMMARY

The present disclosure provides a method and implantable device fortreating pulsatile tinnitus. The method includes imaging cerebral bloodvessels, in particular those adjacent the cochlea to evaluate blood flowin patients with suspected venous etiology. Flow irregularities in theSSIJ are believed to be responsible for pulsatile tinnitus. Thus,imaging these blood vessels allows for identification of an irregularflow pattern having a strong vortex or lateral flow component in theinternal jugular vein at the junction with the sigmoid sinus. The vortexflow pattern is believed to be responsible for sound generation for bothvenous etiologies of pulsatile tinnitus and patients without apreviously identified venous etiology. As such, up to 65% of pulsatiletinnitus may be a caused by this vortex flow pattern in the SSIJ. Themethod according to the present disclosure also includes implanting adevice in the cerebral venous sinuses that disrupts the vortex flowpattern in the SSIJ, thus, removing the sound generation associated withthe blood flow.

The present disclosure also provides a device configured to be implantedin a blood vessel to disrupt a vortex flow pattern while minimizingeffect on the longitudinal flow through the blood vessel. The device maybe implanted transluminally within a portion of the blood vessel havingthe vortex flow. The device includes an outer wall defining a lumen andone or more baffles disposed within the lumen. The location of thebaffle within the lumen interrupts the vortex flow pattern.

According to one embodiment of the present disclosure, an implantabledevice is provided. The implantable device includes: an outer tubularmember defining a longitudinal axis and a lumen, the outer tubularmember having: an outer wall portion having a plurality of first strandsdefining a plurality of first openings therebetween, the outer wallportion having a first porosity. The implantable device also includes aninner baffle portion disposed within the lumen, the inner baffle portionincluding a plurality of second strands defining a plurality of secondopenings therebetween, the inner baffle portion having a second porositythat is lower than the first porosity of the outer wall portion.

According to one aspect of the above embodiment, the inner baffleportion may include a planar surface.

According to another aspect of the above embodiment, the inner baffleportion may include an inner tubular member. The inner tubular member ofthe inner baffle portion is eccentric relative to the outer tubularmember. The implantable device may further include a wire coupled to theinner tubular member, wherein movement of the wire adjusts the secondporosity of the inner baffle member.

According to a further aspect of the above embodiment, at least one ofthe first porosity and the second porosity are adjustable.

According to another embodiment of the present disclosure, a method fortreating pulsatile tinnitus is provided. The method includes: imagingcerebral blood vessels adjacent cochlea to identify irregular blood flowhaving a rotational flow component; and implanting an implantable deviceinto a jugular vein. The implantable device includes: an outer tubularmember defining a longitudinal axis and a lumen, the outer tubularmember having an outer wall portion having a plurality of first strandsdefining a plurality of first openings therebetween, the outer wallportion having a first porosity. The implantable device also includes aninner baffle portion disposed within the lumen, the inner baffle portionincluding a plurality of second strands defining a plurality of secondopenings therebetween, the inner baffle portion having a second porositythat is lower than the first porosity of the outer wall portion, whereinthe inner baffle portion is configured to disrupt the rotational flowcomponent.

According to one aspect of the above embodiment, the inner baffleportion may include an inner tubular member. The method may furtherinclude adjusting a diameter of the inner tubular member to adjust thesecond porosity of the inner baffle portion.

According to a further embodiment of the present disclosure, a methodfor treating pulsatile tinnitus is provided. The method includes:imaging cerebral blood vessels adjacent cochlea to identify irregularblood flow having a rotational flow component; and implanting animplantable device into at least one of a jugular bulb or a jugular veinto disrupt the rotational flow component.

According to one aspect of the above embodiment, the implantable devicemay include a tubular member defining a longitudinal axis and a lumen,the tubular member having an outer wall portion having a plurality offirst strands defining a plurality of first openings therebetween, theouter wall portion having a first porosity.

According to another aspect of the above embodiment, the implantabledevice further includes: an inner baffle portion disposed within thelumen, the inner baffle portion including a plurality of second strandsdefining a plurality of second openings therebetween, the inner baffleportion having a second porosity that is lower than the first porosityof the outer wall portion.

According to a further aspect of the above embodiment, the implantabledevice includes a plurality of tubular members. The plurality of tubularmembers may be arranged in a stacked configuration, such that each ofthe tubular members is arranged in parallel relative to each other. Theplurality of tubular members may be disposed in a grid pattern.

According to yet another aspect of the above embodiment, the tubularmember is at least one of a stent or a stent strut.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present disclosure are described herein withreference to the accompanying drawings, wherein:

FIG. 1 is a three-dimensional time-resolved magnetic resonancevelocimetry image of blood flow through a sigmoid sinus and a jugularvein;

FIG. 2 is a perspective view of an implantable device according to oneembodiment of the present disclosure;

FIG. 3 is a perspective view of an implantable device according toanother embodiment of the present disclosure;

FIG. 4 is a perspective view of an implantable device according to yetanother embodiment of the present disclosure;

FIG. 5 is a perspective view of an implantable device according to afurther embodiment of the present disclosure;

FIGS. 6A and 6B are three-dimensional images of a jugular vein and ajugular bulb each of which has an implantable device disposed therein;

FIG. 7A is a three-dimensional velocimetry image of the jugular vein andthe jugular bulb without the implantable devices of FIGS. 6A and 6Bhaving a blood flow with a rotational component;

FIG. 7B is a three-dimensional velocimetry image of the jugular veinwith the implantable device implanted therein illustrating a disruptionof the rotational component of the blood flow;

FIG. 7C is a three-dimensional velocimetry image of the jugular bulbwith the implantable device implanted therein illustrating a disruptionof the rotational component of the blood flow;

FIG. 8A is a two-dimensional velocimetry image, taken along a verticalplane, of the jugular vein and the jugular bulb without the implantabledevices of FIGS. 6A and 6B having a blood flow with a rotationalcomponent;

FIG. 8B is a two-dimensional velocimetry image, taken along a verticalplane, of the jugular vein with the implantable device implanted thereinillustrating a disruption of the rotational component of the blood flow;

FIG. 9A is a two-dimensional velocimetry image, taken along a verticalplane, of the jugular vein and the jugular bulb without the implantabledevices of FIGS. 6A and 6B having a blood flow with a rotationalcomponent;

FIG. 9B is a two-dimensional velocimetry image, taken along a verticalplane, of the jugular vein with the implantable device implanted thereinillustrating a disruption of the rotational component of the blood flow;

FIG. 9C is a two-dimensional velocimetry image, taken along a verticalplane, of the jugular bulb with the implantable device implanted thereinillustrating a disruption of the rotational component of the blood flow;

FIG. 10A is a two-dimensional velocimetry image, taken along ahorizontal plane, of the jugular vein without the implantable devices ofFIGS. 6A and 6B having a blood flow with a rotational component;

FIG. 10B is a two-dimensional velocimetry image, taken along ahorizontal plane, of the jugular vein with the implantable deviceimplanted therein illustrating a disruption of the rotational componentof the blood flow;

FIG. 11A is a two-dimensional velocimetry image, taken along ahorizontal plane, of the jugular bulb and sigmoid sinus without theimplantable devices of FIGS. 6A and 6B having a blood flow with arotational component; and

FIG. 11B is a two-dimensional velocimetry image, taken along ahorizontal plane, of the jugular bulb with the implantable deviceimplanted therein illustrating a disruption of the rotational componentof the blood flow.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described in detail withreference to the drawings, in which like reference numerals designateidentical or corresponding elements in each of the several views. Asused herein the term “proximal” refers to the portion of an implantabledevice that is closer to a delivery device, while the term “distal”refers to the portion that is farther from the delivery device.

FIG. 1 shows a velocimetry image of irregular blood flow through SSIJ ofa patient suffering from pulsatile tinnitus. In particular, FIG. 1 showsa sigmoid sinus 2, a jugular bulb 3, a jugular vein 4, and a carotidartery 5, and blood flow 6 through the jugular vein 4. Morespecifically, blood flow 6 (as shown by an arrow) includes a vortex flowpattern originating in a superior aspect of the jugular bulb 3 andpropagating down the descending jugular vein 4. It is believed that theblood flow 6, and in particular, its vortical shape, is a source ofsound generation that is picked up by the cochlea and experienced by thepatient as pulsatile tinnitus.

The present disclosure provides a method for treating pulsatile tinnitusby catheterizing the cerebral venous sinuses and implanting a devicethat removes or reduces the rotational component of blood flow withoutsignificantly disrupting the longitudinal component of the blood flowand/or the in-flow from adjacent cortical veins into the larger cerebralor cervical venous structure. Suitable implantable devices according tothe present disclosure may be self-expanding or balloon expandablestents having one or more outer walls and one or more inner bafflesdisposed within a lumen defined by the outer wall.

The implantable devices may be constrained in a catheter, and whenun-sheathed at the target location within the jugular vein or any othervascular location, self-expand so as to contact and push against thevessel walls to prevent migration of the device. In embodiments, thedevice may include one or more attachment members, e.g., hooks, anchors,or teeth, to embed the device in the venous wall. The outer walls of theimplantable device are sufficiently permeable so as not to impede venousingress from the cortical veins or internal jugular vein into the largersinus. Thus, the device is minimally thrombogenic in order to minimizeembolic risk to the systemic venous circulation and the pulmonaryarterial system as a whole, since thrombogenicity could result in parentvenous sinus occlusion. The permeability of the inner baffles of thedevice is low enough such that it sufficiently reduces and/or eliminatesthe rotational component of the vortex flow.

With reference to FIG. 2, an implantable device for reducing and/oreliminating vortex flow is shown. The implantable device is shown as atubular member 10 defining a longitudinal axis “A-A” and a lumen 18extending along the longitudinal axis “A-A.” The tubular member 10includes an outer wall portion 12 and end portions 14 and 16. The outerwall portion 12 includes a plurality of interconnected strands 20′defining a plurality of openings 22′ in between the interconnectedstrands 20′. The outer wall portion 12 is configured to contact thewalls of a vessel such as, e.g., the jugular vein.

The tubular member 10 also includes an inner baffle portion 24 disposedwithin the lumen 18. The inner baffle portion 24 is coupled at one ormore locations, e.g., edges, to the outer wall portion 12. The innerbaffle portion 24 also includes a plurality of interconnected strands20″, which define a plurality of openings 22″ therebetween. The innerbaffle portion 24 is shown as a planar surface bisecting the lumen 18 ofthe tubular member 10. In embodiments, the inner baffle portion 24 mayinclude a plurality of walls interconnected within the lumen 18, thus,separating the lumen 18 into any number of portions, e.g., sub-lumens.

The interconnected strands 20″ forming the inner baffle portion 24 arespaced closer together than the interconnected strands 20′ of the outerwall portion 12, such that the openings 22″ of the inner baffle portion24 are smaller than the openings 22′ of the outer wall portion 12. Thus,the porosity of the inner baffle portion 24 is lower than the porosityof the outer wall portion 12. As used herein, the term “porosity”denotes a ratio between empty space defined by the openings 22′/22″ andspace occupied by the interconnected strands 22′/22″ forming the tubularmember 10. This configuration, namely, a lower porosity of the innerbaffle portion 24 and a higher porosity of the outer wall portion 12,disrupts the vortex flow pattern associated with pulsatile tinnituswhile minimizing the effect on the longitudinal flow through the bloodvessel.

With reference to FIG. 3, another embodiment of an implantable deviceaccording to the present disclosure is shown as a tubular member 110defining a longitudinal axis “B-B” and a lumen 118. The tubular member110 includes an outer wall portion 112 and end portions 114 and 116. Theouter wall portion 112 also includes a plurality of interconnectedstrands 120′ defining a plurality of openings 122′ in between theinterconnected strands 120′. The tubular member 110 also includes aninner baffle portion 124 disposed within the lumen 118. The inner baffleportion 124 is an inner tubular member coupled to an inner surface ofthe tubular member 110 along at least one edge of the inner baffleportion 124 and the outer wall portion 112. The inner baffle portion 124may be eccentric (e.g., two circles that do not share the same centerwith one of the circles being contained within another circle) relativeto the tubular member 110. The inner baffle portion 124 also defines aninner lumen 126, which is also eccentric with the lumen 118. Inembodiments, the inner baffle portion 124 may be concentric with respectto the tubular member.

The inner baffle portion 124 also includes a plurality of interconnectedstrands 120″ defining a plurality of openings 122″. The interconnectedstrands 120″ forming the inner baffle portion 124 are spaced closertogether than the interconnected strands 120′ of the outer wall portion112, such that the openings 122″ of the inner baffle portion 124 aresmaller than the openings 122′ of the outer wall portion 112. Thisconfiguration disrupts the vortex flow pattern associated with pulsatiletinnitus while minimizing effect on the longitudinal flow through theblood vessel similar to the tubular member 10 of FIG. 2

In embodiments, the inner baffle portion 124 may be connected to a wire128 such that after implantation the diameter of the inner baffleportion 124 may be adjusted, which in turn, would adjust the porosity ofthe inner baffle portion 124. This is due to the constriction of theinterconnected strands 120″, thus, decreasing the size of the openings122″. Adjustment of the porosity of the inner baffle portion 124 allowsfor tuning its baffle effect on the rotational component of the bloodflow. Since various blood vessels have different blood flow parametersand properties, it would be useful to tailor the porosity of theimplantable device according to the properties of the blood flow.

With reference to FIG. 4, another embodiment of an implantable deviceaccording to the present disclosure is shown as an implantable device200 having a plurality of tubular members 210 that are arranged in astacked configuration and are parallel to a longitudinal axis “C-C.”Each of the tubular members 210 includes an outer wall portion 212 andend portions 214 and 216 defining a lumen 218. Each of the tubularmembers 210 also includes an inner baffle portion 224. The outer wallportion 212 and the inner baffle portion 224 are formed on the sametubular member 210. However, when the tubular members 210 are joinedtogether as shown in FIG. 4, the inner baffle portions 224 are disposedwithin the vessel lumen, whereas each of the outer wall portions 212contacts the walls of the vessel.

Each of the outer wall portions 212 is formed by a plurality ofinterconnected strands 220′ defining a plurality of openings 222′therebetween. In addition, each of the inner baffle portions 224 isformed by a plurality of interconnected strands 220″ defining aplurality of openings 222″. The interconnected strands 220″ of the innerbaffle portions 224 are spaced closer together than the interconnectedstrands 220′ of the outer wall portions 212, such that the openings 222″of the inner baffle portions 224 are smaller than the openings 222′ ofthe outer wall portions 212. Thus, the inner baffle portions 224 areless porous than the outer wall portions 212, which disrupts the vortexflow pattern associated with pulsatile tinnitus while minimizing theeffect on the longitudinal flow through the blood vessel.

In embodiments, the porosity of the inner baffle portions 224 may beadjusted after implantation of the implantable device 200. This may beaccomplished by varying a diameter of one or more of the tubular members210. The diameter may be adjusted by using a balloon catheter, which isinserted into the lumen 218 of the tubular member 210 whose diameter isto be adjusted and the balloon is then inflated to increase thediameter. Increasing the diameter, in turn, increases the porosity ofthe outer wall portion 212 and the inner baffle portion 224 of thetubular member 210, while decreasing the porosity of the remainingtubular members 210 since all of the tubular members 210 areinterconnected. Adjustment of the porosity of the inner baffle portions224 allows for tuning its baffle effect on the rotational component ofthe blood flow. Since various blood vessels have different blood flowparameters and properties, it would be useful to tailor the porosity ofthe implantable device according to the properties of the blood flow.

With reference to FIG. 5, another embodiment of an implantable deviceaccording to the present disclosure is shown as an implantable device300 having a plurality of tubular members 310, which are arranged in agrid pattern thereby forming a mesh. The tubular members 310 may besubstantially similar to the tubular members 10, 110, and 210 of FIGS.2-4. The tubular members 310 may be disposed substantially in a plane“P.” The implantable device 300 may include a first plurality 310 a oftubular members 310 disposed in a first longitudinal axis and a secondplurality 310 b of tubular members 310 in a second longitudinal axisthat is transverse to the first longitudinal axis, such that the firstand second pluralities 310 a and 310 b intersect each other defining aplurality of openings 311. The tubular members 310 may be stents orstent struts and may have a diameter from about 0.1 mm to about 1.0 mm,in embodiments, from about 0.2 mm to about 0.6 mm. Since the tubularmembers 310 of the implantable device 300 are disposed in a singleplane, the thickness of the implantable device 300 depends on thediameter of the tubular members 310 and may be from about 0.1 mm toabout 1.0 mm, in embodiments, from about 0.2 mm to about 0.6 mm.

Each of tubular members 10, 110, 210, and 310 of FIGS. 2-5,respectively, may be self-expanding stents formed from a shape memorymetal, such as a nickel-titanium alloy (nitinol) or shape memorypolymers, such as those disclosed in U.S. Pat. No. 5,954,744, the entiredisclosure of which is incorporated by reference herein. The stents maybe machined or laser cut from a solid tube of material to form theinterconnected strands according to the present disclosure.

In other embodiments, the tubular members 10, 110, 210, and 310 may bestents formed by braiding metal wire, polymer filaments, or combinationsthereof, into desired shapes described above with respect to FIGS. 2-4.Either of the processes may be adjusted to form tubular members 10, 110,210, and 310 having varying porosity as described above.

The tubular members 10, 110, 210, and 310 of FIGS. 2-5 may also includea plurality of attachment members, such as hooks, anchors, teeth, orother structures configured to grasp the walls of the blood vessel, suchthat the tubular members 10, 110, 210, and 310 are secured within vesseland to minimize migration of the tubular members 10, 110, 210, and 310after implantation.

The tubular members 10, 110, 210, and 310 of FIGS. 2-5 may be deliveredto the target vessels, e.g., cerebral or cervical veins, and inparticular, to a location of maximal sound generation using any suitabletransvenous surgical methods, which may include transfemoral,trans-torcular, or internal jugular vein access. Suitable deliverydevices include balloon catheters and constrained stent deliverycatheters depending on the type of tubular member 10, 110, 210, and 310being used.

The tubular members 10, 110, and 210 may be implanted within the targetvessels such that their longitudinal axes are substantially aligned withthe blood flow or in alternative embodiments, such that theirlongitudinal axes are transverse relative to the blood flow. In otherwords, the tubular members 10, 110, and 210 may be implanted byattaching outer wall portions 12, 112, and 212 to the walls of thetarget vessels in order to align the longitudinal axes of the tubularmembers 10, 110, and 210 with the blood flow. In alternativeembodiments, the tubular members 10, 110, and 210 may be implanted byattaching end portions 14, 16, 114, 116, 214, and 216 to the walls ofthe target vessels in order to place the tubular members 10, 110, and210 across the target vessels and transverse with the blood flow.

With reference to FIGS. 6A and 6B, implantable devices 300 are shownbeing implanted within the jugular bulb 3 and the jugular vein 4. Inembodiments, the implantable devices 300 may be placed within thejugular bulb 3 and/or the jugular vein 4. The implantable devices 300are implanted such that the plane “P” is transverse relative to theblood flow 6 (FIG. 1). In embodiments, the tubular members 10, 110, and210 of FIGS. 2-4 may be also implanted at similar locations within thejugular bulb 3 and the jugular vein 4.

FIG. 7A shows the blood flow 6 from the sigmoid sinus 2, through jugularbulb 3, and the jugular vein 4. As illustrated in region 400, the bloodflow 6 includes secondary flow features, such as rotational components,which result in vortex flow patterns. Thus, rather than having solely aprimary flow component associated with the shape of jugular vein 4,e.g., along a y-axis, the blood flow 6 also includes secondary flowfeatures, e.g., rotational components along an x-axis and a z-axis.

FIG. 7B shows the blood flow 6 being disrupted by the implantable device300, which is placed within the jugular vein 4. The blood flow 6 ischanged after transiting through the implantable device 300, in that thesecondary flow features are diminished as is illustrated by the flowpattern lines being more aligned with the jugular vein 4.

FIG. 7C shows the disruption in the blood flow 6 in response to theimplantable device 300 being placed in the jugular bulb 3. Similarly,the blood flow 6 is modified after transiting through the implantabledevice 300. However, due to the placement of the implantable device 300within the jugular bulb 3, the blood flow 6 is less organized than theblood flow 6 that is disrupted by the implantable device 300 that isimplanted in the jugular vein 4 of FIG. 7B. As shown in FIG. 7C, theblood flow 6 retains some of its vortical shape, albeit it is lesspronounced as compared to the blood flow 6 of FIG. 7A.

FIG. 8A shows a cross-section taken along an x-y plane (FIG. 7A) of theblood flow 6 from the sigmoid sinus 2, through jugular bulb 3, and thejugular vein 4. As illustrated, the blood flow 6 has a higher velocityin a region 402 due to narrowing of the jugular vein.

FIG. 8B, which like FIG. 7B, also shows the blood flow 6 being disruptedby the implantable device 300 placed within the jugular vein 4. Theblood flow 6 is changed after transiting through the implantable device300, in that the there is a reduction in the velocity of the primaryflow component in the region 402. However, the velocity of the bloodflow 6 is increased upstream of the implantable device 300, due to theconstriction of the blood flow 6.

FIG. 9A shows a cross-section taken along an x-y plane (FIG. 7A) of theblood flow 6 from the sigmoid sinus 2, through jugular bulb 3, and thejugular vein 4. As illustrated in region 404, the blood flow 6 includessecondary flow features, having a z-axis velocity component, which isoriented through the x-y plane. The region 404 extends from the jugularbulb 4 through the jugular vein 4.

FIG. 9B shows the effect of implantable device 300, which is disposedwithin the jugular vein 4, on the blood flow 6 within the region 404. Inparticular, the downstream portion of the blood flow 6 of the region 404is modified by the implantable device 300 by reducing the z-axisvelocity component, whereas the upstream portion of the region 404 isunchanged.

FIG. 9C shows the effect of implantable device 300, which is disposedwithin the jugular bulb 3, on the blood flow 6 within the region 404.Similar to the disruption illustrated in FIG. 9B, the implantable device300 within the jugular bulb 3 diminishes the z-axis velocity componentof the blood flow 6 upstream of the implantable device 300, whereas thedownstream portion of the region 404 is unchanged.

FIG. 10A shows a cross-sectional velocimetry slice 406 of the blood flow6 taken along an x-z plane (FIG. 7A). FIG. 10B shows the effect of theimplantable device 300 being placed within the jugular vein 4. Inparticular, the implantable device 300 dampens the velocity of the bloodflow 6, in this case the primary component of the blood flow 6 that isaligned with the jugular vein 4 as illustrated by a lower intensity of avelocimetry slice 408 in FIG. 10B.

FIG. 11A shows a cross-sectional velocimetry slices 410 a and 410 b ofthe blood flow 6 taken along an x-z plane (FIG. 7A) within the sigmoidsinus 2 and the jugular bulb 3, respectively. FIG. 11B shows the effectof the implantable device 300 being placed within the jugular bulb 3. Inparticular, the implantable device 300 dampens the velocity of the bloodflow 6, which in this case is the primary component of the blood flow 6that is aligned with the jugular vein 4 as shown by a lower intensity ofa velocimetry slice 412 b of the jugular bulb 3 in FIG. 11B. However,the velocimetry slice 412 a of the sigmoid sinus 2 is unaffected by theimplantable device 300 due to its placement upstream of the implantabledevice 300.

In addition to causing pulsatile tinnitus, intravascular flowaberrations have been implicated in the development and progression ofcerebral aneurysms, arteriovenous malformations, and stenoses in thegreat arteries of the head and neck, aorta and extremities, amongothers. Thus, the implantable devices according to the presentdisclosure can be implanted in various other vessels to treatpathologies that are responsive to modifying flow dynamics. Identifyingand modifying the flow dynamics responsible for initial development ofthese pathologic states could result in arresting disease development ata very early stage, possibly before the anomaly is even visible. Inpatients where the disease has already begun, implanting devices tochange the flow parameters could immediately modify the risk profile ofthe disease, serve as treatment for the disease, or at very leastdecrease the likelihood of progression of these diseases.

It will be understood that various modifications may be made to theembodiments disclosed herein. In particular, the implantable devicesaccording to the present disclosure may be implanted in any suitableblood vessel where there is a need to modify and/or eliminate rotationalcomponent of the vortex blood flow. Therefore, the above descriptionshould not be construed as limiting, but merely as exemplifications ofvarious embodiments. Those skilled in the art will envision othermodifications within the scope and spirit of the claims appendedthereto.

1. An implantable device comprising: an outer tubular member defining alongitudinal axis and a lumen, the outer tubular member including: anouter wall portion having a plurality of first strands defining aplurality of first openings therebetween, the outer wall portion havinga first porosity; and an inner baffle portion disposed within the lumen,the inner baffle portion including a plurality of second strandsdefining a plurality of second openings therebetween, the inner baffleportion having a second porosity that is lower than the first porosityof the outer wall portion.
 2. The implantable device according to claim1, wherein the inner baffle portion includes a planar surface.
 3. Theimplantable device according to claim 1, wherein the inner baffleportion includes an inner tubular member.
 4. The implantable deviceaccording to claim 3, wherein the inner tubular member of the innerbaffle portion is eccentric relative to the outer tubular member.
 5. Theimplantable device according to claim 4, further comprising a wirecoupled to the inner tubular member, wherein movement of the wireadjusts the second porosity of the inner baffle member.
 6. Theimplantable device according to claim 1, wherein at least one of thefirst porosity and the second porosity are adjustable.
 7. A method fortreating pulsatile tinnitus, the method comprising: imaging cerebralblood vessels adjacent cochlea to identify irregular blood flow having arotational flow component; and implanting an implantable device into ajugular vein, the implantable device including: an outer tubular memberdefining a longitudinal axis and a lumen, the outer tubular memberhaving an outer wall portion having a plurality of first strandsdefining a plurality of first openings therebetween, the outer wallportion having a first porosity; and an inner baffle portion disposedwithin the lumen, the inner baffle portion including a plurality ofsecond strands defining a plurality of second openings therebetween, theinner baffle portion having a second porosity that is lower than thefirst porosity of the outer wall portion, wherein the inner baffleportion is configured to disrupt the rotational flow component.
 8. Themethod according to claim 7, wherein the inner baffle portion includesan inner tubular member.
 9. The method according to claim 8, adjusting adiameter of the inner tubular member to adjust the second porosity ofthe inner baffle portion.
 10. A method for treating pulsatile tinnitus,the method comprising: imaging cerebral blood vessels adjacent cochleato identify irregular blood flow having a rotational flow component; andimplanting an implantable device into at least one of a jugular bulb ora jugular vein to disrupt the rotational flow component.
 11. The methodaccording to claim 10, wherein the implantable device includes: atubular member defining a longitudinal axis and a lumen, the tubularmember having an outer wall portion having a plurality of first strandsdefining a plurality of first openings therebetween, the outer wallportion having a first porosity.
 12. The method according to claim 11,wherein the implantable device further includes: an inner baffle portiondisposed within the lumen, the inner baffle portion including aplurality of second strands defining a plurality of second openingstherebetween, the inner baffle portion having a second porosity that islower than the first porosity of the outer wall portion.
 13. The methodaccording to claim 10, wherein the implantable device includes aplurality of tubular members.
 14. The method according to claim 13,wherein the plurality of tubular members are arranged in a stackedconfiguration, such that each of the tubular members is arranged inparallel relative to each other.
 15. The method according to claim 14,wherein the plurality of tubular members are disposed in a grid pattern.16. The method according to claim 15, wherein the tubular member is atleast one of a stent or a stent strut.
 17. The implantable deviceaccording to claim 1, wherein the inner baffle portion extends along thelongitudinal axis.
 18. The implantable device according to claim 2,wherein the inner baffle portion bisects the lumen.
 19. The methodaccording to claim 7, wherein the inner baffle portion extends along thelongitudinal axis.
 20. The method according to claim 12, wherein theinner baffle portion extends along the longitudinal axis.